Conventionally, representative input methods for desktop, mobile phone, etc. have used a keyboard, a mouse, a track ball, and a joystick. However, in recent years, a touch screen has been mainly used as an easy-to-use and intuitive interface. The touch screen is installed in most of the modern smart devices such as smartphones and has been widely applied in real life such as automatic teller machines and kiosks installed in public places.
Meanwhile, users often use their smartphone on the move or in an unstable environment. Therefore, in this case, a touch input is very inaccurate.
Most of the touch input methods use an absolute coordinate system and require a user to touch a specific position on a screen at a specific time assuming that the user uses the same finger to perform the same operation.
This is caused by limitations in an input method using a mouse and a resistive touch screen system which are widely used in a static environment and thus is not optimal for current smart devices, most of which are equipped with a capacitive touch screen system.
The absolute coordinate system may be suitable for a normal application which does not require a large number of touch inputs but may cause a considerable number of errors in a game which requires a large number of touch inputs. Further, a finger has a relatively larger area than a touch screen, and, thus, a large number of errors may occur according to the absolute coordinate system.
Due to the problems about the touch input methods, there are many limitations in the production of contents.
In this regard, Korean Patent Laid-open Publication No. 2014-0097358 relates to an operation device and describes an absolute coordinate mode and a relative coordinate mode.